Abstract: Improving the quality of patent applications from China in The Belt and Road countries is an inherent requirement for the quality development of the “Belt and Road Initiative” and the construction of a strong intellectual property country. In this paper, seven indicators which involves technology quality and text quality were selected to build the evaluating system of the patent application quality. The article uses the structure entropy method to confirm the weight of the indicators. The patent application quality from China to The Belt and Road countries is obviously higher compared with domestic patent application in China, and the high-quality patents are concentrated in the fields of digital communications, computer technology, organic fine chemistry and electrical machinery. The overall quality of patent application from China in Russia is the highest, which in India is lower however. As for the quality condition of patent application from different provinces, Beijing, Jiangsu, Shanghai, Zhejiang, Hubei are distributed in the “large quantity-high quality” stage